1. Field of the Invention
The present invention relates to a disk drive in which entry of dust etc. into a cartridge accommodating a disk-shaped recording medium is prevented by a sealing member and to a sealing member used for the same.
2. Description of the Related Art
Known is a disk drive in which a disk cartridge accommodating a hard disk is loaded.
This disk drive is provided with a carrier into which the disk cartridge is loaded, a rotation mechanism having a rotation table for clamping and making the hard disk rotate, and a magnetic head mechanism for recording and/or playing back a signal (or information) to or from the hard disk.
In a disk drive, when a disk cartridge is loaded in the carrier, the rotation mechanism enters the cartridge body from a disk drive opening formed in its bottom surface and a magnetic head element enters it from a recording and playback opening positioned close to the outside of the hard disk.
When the hard disk rotates due to the rotation mechanism, the magnetic head element entering into the cartridge body from the recording and playback opening slightly floats due to an air flow generated between the rotating hard disk and the magnetic head element and is operated so as to move across the inner and outer circumferences of the hard disk to record and/or play back a signal with respect to the hard disk.
Summarizing the problem to be solved by the invention, hard disks include ones having a diameter of about 65 mm and increased in capacity so as to enable recording of several gigabytes of information or signals.
In such hard disks, when recording or playing back dust and other foreign matter, the magnetic head element is operated so as to move across the inner and outer circumferences of the hard disk in a state where the magnetic head element floats several tens of nanometers from the hard disk.
At this time, if the hard disk is rotated at a high speed by the rotation mechanism, air is sucked into the cartridge body from the disk drive opening in which the rotation mechanism enters. For this reason, dust etc. is liable to invade the cartridge body due to the air flow.
In a disk drive for recording or playing back information or a signal in the state with magnetic head element floating from the hard disk by tens of nanometers, if dust etc. invading the cartridge body from the disk drive opening deposits on the hard disk, the magnetic head element collides with the dust, so it becomes difficult to reliably record and play back the information or signal to and from the hard disk.
Further, if dust etc. deposits on the hard disk, the amount by which the magnetic head element floats from the hard disk fluctuates, so it becomes difficult to reliably record the information or signal on the hard disk.
Note that Japanese Unexamined Patent Publication No. 10-188510 discloses an invention of such a disk drive.
This publication discloses to seal the outer circumference of a hub of the loaded disk cartridge, for example, to seal the space between the periphery of the hub of the cartridge and a motor housing of the spindle motor by a resilient sealing member having a tapered surface contacting the bottom surface of the cartridge.
In this publication, however, the sealing member was fixed to the motor housing etc. beneath the inclined resilient tapered surface, so attachment of the sealing member was troublesome.
A first object of the present invention is to provide a disk drive capable of preventing air containing the dust from invading a cartridge from an opening in a bottom surface of a cartridge at the time of rotation of a disk-shaped recording medium loaded in the disk drive and a sealing member useable in this disk drive.
A second object of the present invention is to provide a disk drive capable of reducing the trouble of attaching the sealing member.
To attain the above objects, according to a first aspect of the present invention, there is provided a disk drive having a carrier in which is loaded a cartridge in which a disk-shaped recording medium is rotatably accommodated and in which an opening for exposing a center portion of the disk-shaped recording medium is formed in its bottom surface, a rotation table which enters from the opening of the cartridge loaded in the carrier, clamps the disk-shaped recording medium at the center portion and makes the disk-shaped recording medium rotate, and a resilient sealing member which is attached to the carrier and prevents air containing dust from being sucked into the cartridge from the opening due to rotation of the disk-shaped recording medium, wherein the sealing member has an annular base portion and a lip having a shape projecting from the annular base portion and flaring outward, the lip is pushed against the bottom surface of the cartridge so as to surround the opening of the loaded cartridge, and the base portion has a part located inward from the lip, which part is attached to the carrier.
In the disk drive according to the present invention, preferably provision is further made of a plurality of projections for positioning the cartridge, each of the plurality of projections has a head contacting the bottom surface of the cartridge, the base portion has a plurality of through holes corresponding to the plurality of projections in the part located inward from the lip, and the sealing member is attached to the carrier by the plurality of projections penetrating through the corresponding plurality of through holes.
In the disk drive according to the present invention, more preferably the head of each projection has a diameter larger than that of the through hole to an extent enabling the projection to be fit into the through hole.
In the disk drive according to the present invention, preferably the lip comprises first and second lips, the first and second lips project from a top surface of the base portion, the first lip is located outside from the second lip, a height of the first lip from the center portion of the base portion is higher than the height of the second lip from the center portion of the base portion when the cartridge is not loaded, and the first and second lips contact the bottom surface of the cartridge and the heights of the first and second lips from the center portion of the base portion are the same when the cartridge is loaded.
In the disk drive according to the present invention, more preferably the first and second lips are substantially parallel, a length of the first lip is longer than the length of the second lip, and the heights of the first and second lips from the center portion of the base portion are substantially the same when the cartridge is not loaded.
In the disk drive according to the present invention, alternatively the lip has first and third lips, the first lip projects from the top surface of the base portion and contacts the bottom surface of the cartridge when the cartridge is loaded, and the third lip projects from a bottom surface of the base portion and contacts the carrier.
In the disk drive according to the present invention, more preferably the first and third lips are formed symmetrically or substantially symmetrically to each other about the base portion.
In the disk drive according to the present invention, alternatively the lip has first, second, third, and fourth lips, the first and second lips project from the top surface of the base portion and contact the bottom surface of the cartridge when the cartridge is loaded, the third and fourth lips project from the bottom surface of the base portion and contact the carrier, the first lip is located outside from the second lip, the third lip is located outside from the fourth lip, the height of the first lip from the center portion of the base portion is higher than the height of the second lip from the center portion of the base portion and the height of the third lip from the center portion of the base portion is higher than the height of the fourth lip from the center portion of the base portion when the cartridge is not loaded, and the first and second lips contact the bottom surface of the cartridge, the heights of the first and second lips from the center portion of the base portion are the same, and the heights of the third and fourth lips from the center portion of the base portion are the same when the cartridge is loaded.
In the disk drive according to the present invention, more preferably the first and second lips are substantially parallel to each other, the third and fourth lips are substantially parallel to each other, the length of the first lip is longer than the length of the second lip, the length of the third lip is longer than the length of the fourth lip, and the heights of the first and second lips from the center portion of the base portion are substantially the same and the heights of the third and fourth lips from the center portion of the base portion are substantially the same when the cartridge is not loaded.
In the disk drive according to the present invention, more preferably the first and third lips are formed symmetrically or substantially symmetrically to each other about the base portion, and the second and fourth lips are formed symmetrically or substantially symmetrically to each other about the base portion.
In the disk drive according to the present invention, preferably the base portion has a projection for positioning of the cartridge, the related positioning projection is formed along the inner circumference of the base portion, and the height of the projection from the center portion of the base portion is lower than the height of the lip from the center portion of the base portion when the cartridge is not loaded and the same as the height of the lip from the center portion of the base portion when the cartridge is loaded.
In the disk drive according to the present invention, preferably the base portion of the sealing member is fixed to the carrier via a filter for filtering the air and the air filtered by the filter is sucked from the opening at the time of rotation of the disk-shaped recording medium.
In the disk drive according to the present invention, preferably the lip has a vent hole through which the air passes, a filter for filtering the air is attached so as to cover the vent hole, and the air passing through the vent hole and the filter is sucked from the opening at the time of rotation of the disk-shaped recording medium.
In the disk drive according to the present invention, more preferably the filter is attached to the outer circumference of the lip and the air filtered by the filter passes through the vent hole and is sucked from the opening.
In the disk drive according to the present invention, more preferably the cartridge has a shutter, the shutter is closed when the cartridge is not loaded and is opened to expose the opening when the cartridge is loaded, and the lip of the sealing member is pushed against the periphery of the opening in a flat part appearing due to movement of the shutter when the cartridge is loaded.
In the disk drive according to the present invention, more preferably provision is further made of an optical pickup, the disk-shaped recording medium is an optical disk, and the opening exposes the center portion and exposes a part of the disk-shaped recording medium to which a laser beam from the pickup is focused when the cartridge is loaded.
In the disk drive according to the present invention, alternatively more preferably provision is further made of an optical pickup and a magnetic head element, the disk-shaped recording medium is a magneto-optic disk, the opening has a first opening formed in the bottom surface of the cartridge and a second opening formed in the top surface of the cartridge, the first opening exposes the center portion and exposes a part of the disk-shaped recording medium to which a laser beam from the optical pickup is focused when the cartridge is loaded, the second opening exposes a part facing the magnetic head element when the cartridge is loaded, the sealing member comprises first and second sealing members, the first sealing member seals the space between the periphery of the first opening and the carrier, and the second sealing member seals the space between the periphery of the second opening and the carrier.
In the disk drive according to the present invention, alternatively more preferably provision is further made of an optical pickup and a magnetic head element, the disk-shaped recording medium is a magneto-optic disk, the opening has a first opening formed in the bottom surface of the cartridge and a third opening formed in a side surface of the cartridge, the first opening exposes the center portion and exposes a part of the disk-shaped recording medium to which the laser beam from the optical pickup is focused when the cartridge is loaded, the third opening has inserted into it the magnetic head element when the cartridge is loaded, and the sealing member seals the space between the periphery of the first opening and the carrier.
In the disk drive according to the present invention, more preferably the sealing member is made of a silicone rubber, and the disk-shaped recording medium is a removable hard disk.
A sealing member according to the present invention is a resilient sealing member having an annular base portion and a lip having a shape projecting from the base portion and flaring outward, the base portion has a part located inward from the lip, and a plurality of through holes are formed in the related part.
In the sealing member according to the present invention, preferably the lip comprises first and second lips, the first and second lips projected from one surface between the top and bottom surfaces of the base portion, the first lip is located outside from the second lip, and the height of the first lip from the center portion of the base portion is higher than the height of the second lip from the center portion of the base portion.
In the sealing member according to the present invention, more preferably the first and second lips are substantially parallel to each other, the length of the first lip is longer than the length of the second lip, and the heights of the first and second lips from the center portion of the base portion are substantially the same.
In the sealing member according to the present invention, more preferably the lip has first and third lips, the first lip projects from the top surface of the base portion, and the third lip projects from the bottom surface of the base portion.
In the sealing member according to the present invention, more preferably the first and third lips are symmetrical or substantially symmetrical to each other about the base portion.
In the sealing member according to the present invention, preferably the lip has first, second, third, and fourth lips, the first and second lips project from the top surface of the base portion, the third and fourth lips project from the bottom surface of the base portion, the first lip is located outside from the second lip, the third lip is located outside from the fourth lip, the height of the first lip from the center portion of the base portion is higher than the height of the second lip from the center portion of the base portion, and the height of the third lip from the center portion of the base portion is higher than the height of the fourth lip from the center portion of the base portion.
In the sealing member according to the present invention, more preferably, the first and second lips are substantially parallel to each other, the third and fourth lips are substantially parallel to each other, the length of the first lip is longer than the length of the second lip, the length of the third lip is longer than the length of the fourth lip, the heights of the first and second lips from the center portion of the base portion are substantially the same, and the heights of the third and fourth lips from the center portion of the base portion are substantially the same.
In the sealing member according to the present invention, more preferably the first and third lips are formed symmetrically or substantially symmetrically to each other about the base portion, and the second and fourth lips are formed symmetrically or substantially symmetrically to each other about the base portion.
In the sealing member according to the present invention, more preferably the lip has a hole, and a filter for filtering the air is attached so as to cover the related hole.
In the sealing member according to the present invention, more preferably the filter is attached to the outer circumference of the lip.
In the sealing member according to the present invention, it is also possible to employ a structure in which for example the base portion forms a band shape having the same width or substantially the same width along the periphery of a predetermined shape, and the predetermined shape is the same or substantially the same as a square, oval, or a circle.
In the sealing member according to the present invention, it is also possible to employ a structure in which for example the base portion forms a band shape having the same width or substantially the same width along the periphery of a predetermined shape, and the predetermined shape is the same or substantially the same as a shape of a rectangle with one short side removed and an arc of a semi-circle having a diameter equal to the length of the related short side connected to the ends of the two long sides.
The resilient sealing member is attached to the carrier in which the cartridge is loaded. This sealing member prevents air containing dust from being sucked into the cartridge from the opening by the rotating disk-shaped recording medium, therefore it is possible to improve the reliability of the recording and playback of a signal and the reliability of the disk drive.
The sealing member has an annular base portion and a lip having a shape projecting from the base portion and flaring outward. This lip is pushed against the bottom surface of the cartridge so as to surround the opening of the loaded cartridge, a front end of the lip flares outwardly, and the bottom surface of the cartridge and the inclined surface of the lip contact for the sealing.
The base portion has a part located inward from the lip. By attaching the related part to the carrier, the trouble of attachment of the sealing member can be reduced compared with the case where the member is attached beneath the inclined resilient lip.